IMI Negev
The Negev is an Israeli 5.56 mm light machine gun, developed by Israel Military Industries Ltd. (IMI) of Ramat HaSharon (now Israel Weapon Industries), as a replacement for the 5.56 mm Galil ARM light machine gun, whose barrel would overheat easily during sustained fire. Design work on this new indigenous firearm began in 1985, and it was officially adopted by the Israeli Defense Forces (IDF) in 1997. In 2012, IWI introduced the new Negev NG7, in 7.62mm calibre, to become the standard issue for the IDF. Design details The Negev is a gas-operated automatic firearm that uses propellant gases from the barrel to cycle a short-stroke gas piston operating system under the barrel and a rotary bolt locking mechanism. The bolt itself features 4 radial locking lugs that engage the barrel extension and its rotation is controlled by a pin on the bolt body, which rides inside a camming guide machined into the bolt carrier. The bolt contains a spring-powered casing extractor unit, while a lever ejector is housed inside the receiver (it is rotated by the recoiling bolt carrier). Gas regulator The Negev’s adjustable gas regulator has three settings: “1” is used exclusively when feeding from a magazine (the weapon’s rate of fire in this mode is 850–1,150 rounds/min), setting “2” is used in normal operating conditions when feeding from a belt (rate of fire: 850–1,150 rounds/min) and setting “3” which is used under adverse operating conditions, such as in the presence of dust, dirt or heavy fouling (cyclic rate of fire is 950-1,150 rounds/min). Early prototypes used a different 3-position gas adjustment system: setting “1”—normal operation; setting “2”—for adverse environmental conditions; and setting “3”—isolates the gas system, used to launch rifle grenades with the use of a grenade-launching blank cartridge drawn from a special 12-round magazine (from the Galil rifle). Striker The Negev is striker-fired, where the bolt carrier assembly acts as the striker. The light machine gun fires from an open bolt position. A lever-type fire control selector switch is provided (“A”—full-automatic fire, “R”—semi-automatic fire), installed on the left side of the pistol grip, which doubles as a manual safety against accidental firing. The safe “S” position disables the sear mechanism (which makes it impossible to cock the bolt carrier), by lifting the lever responsible for holding the bolt carrier in the forward position and disconnects the trigger mechanism from the sear. The weapon can be secured safe regardless of the position of the bolt carrier group. The cocking handle is equipped with a ratcheting mechanism that immobilizes the partially cocked bolt carrier. Ammunition The Negev feeds from an M27 disintegrating, open-link ammunition belt, carried in a 150-round fabric container that clips into the magazine well or alternately from a 35-round box magazine from the Galil assault rifle or a 30-round STANAG magazine from the M16 rifle (with the use of an adapter). 200-round ammunition belt containers are also available. Belted ammunition is introduced into the feed tray port from the left side, while the magazine is inserted vertically into the magazine well at the base of the receiver. The feed system uses a pawl feeding mechanism, driven by the recoiling bolt carrier, but the belt is moved only during the rearward movement of the bolt carrier. The non-reciprocating charging handle is located on the right side of the weapon. Barrel The Negev has a quick-change chrome-lined barrel that is manufactured using a cold hammer forging process. The barrel is fitted with a slotted flash suppressor and a fixed carry handle, which is used to transport the weapon and change-out an overheated barrel. The barrel can be changed only after lifting open the feed tray cover. During the weapon’s initial development a barrel with a 1 in 305 mm (1:12 in) rifling twist rate was also planned, adapted for the lightweight M193 cartridge. Additionally, a multifunction muzzle device was designed, used to launch rifle grenades. Sight The Negev’s iron sights (closed-type) consist of a front post (adjustable for both windage and elevation) and a rear aperture sight with an elevation adjustment drum, with 300 to 1,000 m range settings. For night-time operation the weapon is equipped with gaseous tritium-illuminated vials (supplied by Betalight): one installed in the front sight post, and two—on a notch sight under the standard aperture sight arm (before use, the rear sight leaf is pivoted forward to expose the night notch sight). A rail is integrated into the receiver top cover that allows optical day and night-time sights to be mounted to the weapon. The barrel can also be optionally fitted with mounting hardware that would allow the Negev to mount a laser pointer or reflex sight. The machine gun has a metal side-folding (right side) stock and a removable bipod, installed to the forward end of the handguard and folded under the handguard when stowed. The receiver also has slots and hooks used to secure the weapon to vehicle mounting hardware. Cartridges The Negev uses the 5.56x45mm NATO cartridge and is optimized for the SS109 bullet. Field maintenance involves stripping the weapon down to six main groups: the barrel, stock, bolt carrier, bolt, bipod and return mechanism. All parts, including the quick-change barrels, are fully interchangeable. Variants The Negev Commando is a shorter and lighter version of the standard Negev light machine gun, known also as the Assault Negev. After the privatization of the Magen Light Weapon Division when company's name was changed to Israel Weapon Industries (IWI) the name of the Negev Commando was changed as well to Negev SF (Special Forces). On this model the barrel is shortened to 330 mm (13.0 in), a bipod is optional and the stock folds to the left side, so that the overall length with the butt folded is only 680 mm (26.8 in). For the assault role a side-mounted forward grip is provided for the user's left hand, allowing the weapon to be fired from the hip. Weight of the Negev SF with a 150-round drum is 9.55 kg (21.1 lb). Vehicle, AFV and helicopter mountings are available. This variant underwent trials with IDF special forces during late 1998. In March 2012, IWI introduced the Negev NG7, a derivative of the Negev machine gun in caliber 7.62mm NATO. Category:Weapons